Optical coherence tomography shows variability in port wine birthmark density, size

Key takeaways:

• Results showed a high degree of variability in the density and size of vessels within and between port wine birthmarks.
• Variability ranged from resembling uninvolved skin to very dilated.

Optical coherence tomography may be able to guide treatment for port wine birthmarks that show wide variability in vessel density and size, but improvements are needed, according to a study.

“There is very wide variability in the number of vessels and in the size of vessels in port wine birthmarks,” Kristen M. Kelly, MD, professor in the departments of dermatology and surgery and chair of the department of dermatology at University of California, Irvine, told Healio.

While the standard of treatment for port wine birthmarks is laser, the variability of vessel size and depth between and within these birthmarks makes them very difficult to treat and clear.

Using optical coherence tomography (OCT) to measure blood vessel density and modal vessel diameter, the authors assessed variability in blood vessel characteristics within and between individual port wine birthmarks among 10 patients (average age, 39.8 years; age range, 8-72 years; male, n = 6) with 15 birthmarks total.

Results showed that there was great variability in the density and size of vessels seen between port wine birthmarks, with shallow dermal depths (0.15 mm to 0.2 mm) being the only depths into the skin where average ratios of vessel density in affected skin were consistently greater than in control skin.

“I have to say, the degree of variability surprised me,” Kelly said. “We saw some port wine birthmarks with vessels that were the size of what we would see in uninvolved skin and then there were ones where it was very dilated.”

Because of this, Kelly explains that if clinicians are going to use OCT to guide treatment, it will require many measurements as well as measurements at each visit.

According to Kelly, the ideal situation would be that dermatologists have a device that could rapidly take measurements of each spot and automatically choose laser settings based on those measurements; however, this type of technology does not currently exist. Nevertheless, that does not stop clinicians from hoping for the future.

“My hope really is that ultimately we'll use this to be able to guide treatments,” Kelly told Healio. “But it will be tricky. It requires engineers and clinicians, patients and scientists all working together to be able to optimize this in a way that will be most helpful to patients.”